Expanded metal lath



Patented oci; 15, 1940 UNITED s-TATES- PATENT) OFFICE EXPAN DED METAL/LATH Edwin w. Miller, Glendale', c1if.,assig`n0r.to

v EdmundP, Burke, Los Angeles, Calif.

Application April 30, '1938, Serial No. 205,266 v sclaims."(01.72-11.17),`A` l i' l My invention relates to expanded'metal lath andhasfor its object to provide an expanded metal lath which is stronger,more rigid, more' beautiful in design, and more practical and ef- 6cient than present designs.

In the'nrnanufacture of myimproved metal lath, the finished product ismade of sheet metal so f shoulda' differ. sign resulting is that of rowsof vtriangles having slitted and stretched or expanded that theA de.-

10 straight, "stretched sides, each row having said trianglesalternately in opposite directions, the

two sides of adjacent triangles forming also the two sidesof a reversedvtriangle therebetween.

In this vform the base of each triangle isV formed f l5 byftwo shortlengths of material andeach of the two sides of a single length ofmaterial. lThe reticular sheet of expanded metal is character ized by atriangular network in which the bases of' adjacent triangles areiin`st`raight, stretched strands or'lines, and thesides of saidtriangles form parallel lines diagonally positioned in oppositedirections. The result isk such rigidity that said metal lath cannotbestretched transversely, or in the line of the parallel bases, which arestretched taut, or vertically because of the diagonal positions of lthelong sides of the triangles formed as the slitted metal sheet isexpanded or stretched to tautness in the formation of the metal lath.Moreover, the lath of this in- 80 vention resists compressive .forcesapplied in the plane of theexpanded metal sheet either later-A ally,transversely or along diagonals to the edges of the sheet.

In order to more fully explain my invention, I have illustrated anembodiment of the same on the accompanying sheet of drawings, in which:

Figure' 1 is a section of sheet metal shown slitted or cut as the firststep in the formation of my improved metal lath; if) Figure 2 is thesame sheet partly expanded or pulled apart; Y

Figure 3 is an enlarged view of a portion of a metal lath embodying myinvention; and Fig.

4 is a plan view of that shown in Fig.

45 Referring in more detail to the drawing, a

section of a sheet of metal suitable for the manufacture of lath isindicated at 5. This sheet is provided with parallel rows of slits inalignment,

such as the slits 6 and 1, theslits in each row being interrupted byuncut spaces such as the spaces 6' and 'l'. Generally, these uncutspaces between opposing ends 0f slits in a row are shorter than thelength of the slits in such row. The uncut spaces or gaps in alternaterows are 55 in transverse alignment so that the uncut spaces .6* areindicated man alignment transvrsem A the rows of slits. vThe uncutspaces in vintermey ld iate rows are'also intransverse alignment whichis different from` vthe 'alignment ofv l the spaces 6'.LThe'vopposingends of aligned "slitsinV 5, theinterrnediate-rows shouldoverlap-a slitf-in'f an adjacent row and the amount' offoverlap",lv,'For example, I6 and l'x'denotef f the opposing ends of :slits 6ina-row, such opi? posing endsl 4being separated bynan uncut por.,l 10

tion '6'. These opposingendsfo'f the slits`-6 over-L,y lap the yadjacentslit 1 by' "distances diffeging from Veachv other. rIt will be noted`thatthe end" I6 of the slit 6 overlapsthe slit 1 byfa very `materialdistance whereas theA end rlli of '.thealiged u t slit` 6 overlapsthe'slit 'l by a shorterir'dis'tance;

. Pairs of gapsA` or uncut portions are thus formed,

each pair being designated', and such gapsformV the junctions'finftheexpandedA sheet as indl` cated in"Fig. 2in particular'. 20 As'saidfslitted sheet is 'expanded lorpulled said slits open up, asindicated in Fig. 2, and this is done by pulling the left hand edge out,oraway from the sheet, and the right hand edge back, or, with thedrawing lying at on the desk, the 25 left hand edge is pulled up and theright hand edge would be pulled down, or in the'opposite di- ,rection.This results inseparating the sheet rst into the form shownin Fig. 2,and then into the nished'form shown in Fig.

The short connecting portions, designated 9, 9, between the twotransverse rows of gaps, as they are stretched form the straight base,or short sides, of the triangles, as will be clear from Fig.

3. The base of each triangle is thus common to $5 portions of the baseof two other triangles. The" long connecting portions, designated I0,I0, form the long sides of the triangles. It is to be noted also thatthese 'long sides of the triangular forms are in diagonal alinement inopposite directions o and that thev short connecting portions 9, 9, arein straight lines, and that-between said straight baselines are thetriangular forms alternately in opposite positions. The precise shape ofthe, triangles formed in the expanded lathV depends l t It is to benoted that the resulting expanded sheet is substantially fiat, the sidesand bases of all triangles lying in a common plane. During the expandingof the sheet in Width, the length of the sheet has been reduced but allsides and bases of the triangles have been subjected to substantiallythe same amount of stress during ex-` pansion. Y

While I have shown and described in detail one practical embodiment ofaware that changes may be made in details of construction withoutdeparting from the spirit thereof, and I do not, therefore, lirnit myinf` vention to the showing rnade, except as I may be limited by thehereto appended claims forming a part of my application.

I claim:

1. A sheet metal blank slitted with parallel; f

cuts, alternate cuts being interrupted in 'differ` ent positionslongitudinally of said cuts, the interruptions of alternate cuts formingone row transversely of said cuts and the interruptions of the otheralternate cuts` forming another row transverselyof said cuts, said tworows of un-v cut portions transversely of the cuts constituting a pair,the pairs of uncut portions being fur-gv ther apart thanthe rowsV ofeach pair, whereby when said sheet is expanded laterally, the strandsbetween said cuts form the long sides of triangular forms and theshorter strands form the bases of said triangular forms, there being twoi rows of overlapping triangular forms. between two lines of bases. A 5,`2. Expanded metal lathmade of sheet meta sltted with parallel cuts withshort interrupg the interruptions of alternatel tions in said cuts, cutsVforming rows of interruptionsv transversely of said sheet metal, saidrows being in pairs, and the pairs of rows being further apartlongitudinally than the interruptions of each pair, Wheremy invention, Iain-i`V 'ing vjoined substantially at its mid .,ternate rows being intransverse alignment; the

uncut spaces in intermediate rows being in a different transversealignment, the opposing ends of aligned slits in said intermediate rowsoverlapping a slit in an adjacent row by distances differing from eachother.

4. As an article of manufacture, a substantially flat reticular sheetVof expanded metal, the

Ametal forming triangles, such triangles being ari'angedin rows withtheir bases in a substantiallyfstraight line. the base of each trianglebeing common to portions of the bases of two adjacent triangles.

5. As an article of manufacture, a substantially at reticular sheet ofexpanded metal, the metal forming triangles, such triangles beingarranged in rows, the base of each triangle be- Y point to theintersection of two sides of adjacent triangles.

\ 6. An larticle, of manufacture substantially as shown and describedand consisting of a substantially at sheet of reticulated metal, the

reticulations forming triangles, the base of each triangle being commonto portions of the bases 'yf-oi, two adjacent triangles, said basesforming straight lines in alignment with each other, the

sides of said triangles being in substantially diagonal alignmentwhereby the sheet has rigidity and strength against deformation invarious directions.

. EDWIN W. MILLER.

